Examples of laminated ceramic electronic components include laminated ceramic capacitors. The increased electrostatic capacitance per unit volume, that is, the ability to acquire higher capacitance in spite of being smaller in size is desired for laminated ceramic capacitors in the case of using the capacitors as surface-mounted components. In order to enhance the reduction in size and the increase in capacitance, it is typically effective to enhance the reduction in layer thickness for each of ceramic layers and internal electrodes, and the increase in the number of the internal electrodes located between the ceramic layers.
However, the increased number of the layers increases the ratio of the internal electrodes per unit volume of the laminated ceramic capacitor. As a result, the difference in the temperature of sintering shrinkage in a firing step between the ceramic layer section and the internal electrode section has a significant influence, which makes delamination likely to be caused.
In addition, the ceramic constituting the ceramic layer section and the metal constituting the internal electrode section are different from each other in coefficient of thermal expansion. Therefore, the laminated ceramic capacitor obtained through the firing step has internal stress caused by the difference in coefficient of thermal expansion. This internal stress is further increased as the ratio of the internal electrodes is increased by the increase in the number of layers, and thus is a cause of making cracks likely to be caused when thermal stress (thermal shock) is applied.
In order to solve these problems, for example, Japanese Patent Application Laid-Open No. 2004-111698 (Patent Document 1) discloses glass phases extending in a columnar fashion in the thickness direction of internal electrodes, which are distributed in scraps. This configuration will be described in more detail with reference to FIG. 7. FIG. 7 is a cross-sectional view illustrating a partial enlargement of a laminated body 4 to serve as a component main body of a laminated ceramic capacitor.
The laminated body 4 has a stacked structure including a plurality of ceramic layers 2 stacked and internal electrodes 3 located between the ceramic layers 2. The internal electrodes 3 mainly include a metal sintered body 6, and have several voids 7 observed, while columnar glass phases 8 extending in a columnar fashion in the thickness direction are distributed in scraps in the internal electrodes 3.
The glass phases 8 are formed in the firing process for obtaining the laminated body 4. When a glass component is contained in a conductive paste for the internal electrodes 3, a glassy substance is deposited in the internal electrodes 3 and at the interface section between the internal electrodes 3 and the ceramic layers 2 in the process of firing, and this deposited glassy substance partially forms the columnar glass phases 8.
The glassy substance deposited as described above suppresses the shrinkage of the internal electrodes 3, reduces thermal stress at the interfaces between the internal electrodes 3 and the ceramic layers 2, and makes the internal electrodes 3 and the ceramic layers 2 likely to slide on each other at the interfaces. Thus, stress which causes delamination can be relaxed to make structural defects such as delamination and cracking less likely to be caused.
However, the technique described in Patent Document 1 forms the columnar glass phases 8 so as to penetrate in the thickness direction of the internal electrodes 3, and thus causes the internal electrodes 3 to be broken off at least in the sections with the columnar glass phases 8 present. As a result, in the case of the laminated ceramic capacitor, situations are caused against the demand for the increase in capacitance, such as leading to a reduction in electrostatic capacitance.
While the laminated ceramic capacitor has been described above, laminated ceramic electronic components other than laminated ceramic capacitors can also encounter similar problems.    Patent Document 1: Japanese Patent Application Laid-Open No. 2004-111698